ABSTRACT
The testing of the prisms followed the requirements of Canadian Standards Association (CSA)-S304-14 and imposed a reduction of 9.47% to the measured compressive strength of the specimens when testing a three-coursehigh prism instead of a five-course-high prism. Concrete masonry's sister material, concrete, applies no reductions when testing specimens of height to diameter ratio of 2.0. Face shell loading was used to simulate the load path in hollow block masonry walls which are laid with mortar on the face shells only, with no cross-bed mortaring. The objective of both the CSA-A165.1-14 and CSA-S304-14 is to obtain a compressive strength for the block unit or masonry prism that will exceed the specified compressive strength 95% of the time, assuming that strength has a Gaussian distribution. The dimensions of a three-course- high block prism were used to allow comparison between the behaviour of the concrete and the behaviour of the concrete block masonry prisms.
